The Earth Defense Force knows her as "Miss Ra," the Rara Army's spokeswoman/mascot, but when Kazuki is injured and trapped behind enemy lines, it's revealed that she is Mitsuki Sanada's counterpart in the parallel world, the daughter of Hiroshi and Ayuko Rara.

Mitsuki Rara could very well be Mitsuki Sanada's direct opposite. She's quiet, easily embarrassed and gentle; she personally nurses Kazuki back to health. However, she places herself in a trance to play Miss Ra, becoming a ruthless warrior. When she finds out that Kazuki is an enemy pilot, she launches him away in an escape pod, remembering the time he could have killed Miss Ra, but saved her instead.

Mitsuki is later brainwashed into piloting Himiko, one of the most powerful robots created. After Kazuki saves her, she resists returning home, eventually becoming a Core Robot pilot for the EDF. She comes the closest to capturing Kazuki's heart; the two almost go out on a date, which is unfortunately cancelled by U.N. officers intent on sending her home.

When Zinv is destroyed and the worlds merge, Mitsuki lives in the Sanada home, even though her parents live right next door.